In the art of identifying objects or animals, increasing use is recently being made of chip transponders having an associated small antenna. Recently chip transponders have come into use which are placed in a badge, card or similar flexible sheet. An antenna for use in this application must in general have a flat and flexible magnetic core around which the antenna winding may be fitted, and yet have a high quality factor to provide specific antenna characteristics. The ferrite elements which have been used in the past are relatively hard and insufficiently flexible so that consequently, they will break when bent.